• Restorative Dentistry and Endodontics
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• 제25권3호
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• pp.321-337
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• 2000

Dental caries, one of the most frequent dental disease, become larger because it can be thought as a simple disease. Further more, it can progress to unexpected root canal therapy with fabrication of crown that needs reduction of tooth structure. Base is required in a large caries and ZOE, ZPC, glass ionomer are used frequently as base material. They, with restorative material, can affect the longevity of the restoration. In this study, we assume that the mandibular 1st molar has deep class I cavity. So, installing the 3 base material, 3 kinds of fillings were restored over the base as follows; 1) amalgam only, 2) amalgam with ZPC, 3) amalgam with ZOE, 4) amalgam with GI cement, 5) gold inlay with ZPC, 6) gold inlay with GI cement, 7) composite resin only, 8) composite resin with GI cement. After develop the 3-dimensional model for finite element analysis, we observe the distribution of stress and temperature with force of 500N to apical direction at 3 point on occlusal surface and temperature of 55 degree, 15 degree on entire surface. The analyzed results were as follow : 1. Principal stress produced at the interface of base, dentin, cavity wall was smallest in case of using GI cement as base material under the amalgam. 2. Principal stress produced at the interface of base, dentin, cavity wall was smaller in case of using GI cement as a base material than ZPC under gold inlay. 3. Composite resin-filled tooth showed stress distributed over entire tooth structure. In other words, there was little concentration of stress. 4. ZOE was the most effective base material against hot stimuli under the amalgam and GI cement was the next. In case of gold inlay, GI cement was more effective than ZPC. 5. Composite resin has the small coefficient of thermal conductivity. So, composite resin filling is the most effective insulating material.

• Journal of Periodontal and Implant Science
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• 제42권2호
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• pp.39-44
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• 2012

Purpose: Special care is necessary to avoid invading important anatomic structures during surgery when presurgical planning is made based on radiographs. However, none of these types of radiography represents a perfect modality. The purpose of this study was to determine the reliability of presurgical planning based on the use of two types of radiographic image (digital panoramic radiography [DPR] and cone-beam computed tomography [CBCT]) by beginner dentists to place implants, and to quantify differences in measurements between radiographic images and real specimens. Methods: Ten fresh cadavers without posterior teeth were used, and twelve practitioners who had no experience of implant surgery performed implant surgery after 10 hours of basic instruction using conventional surgical guide based on CBCT or DPR. Two types of measurement error were evaluated: 1) the presurgical measurement error, defined as that between the presurgical and postsurgical measurements in each modality of radiographic analysis, and 2) the measurement error between postsurgical radiography and the real specimen. Results: The mean presurgical measurement error was significantly smaller for CBCT than for DPR in the maxillary region, whereas it did not differ significantly between the two imaging modalities in the mandibular region. The mean measurement error between radiography and real specimens was significantly smaller for CBCT than for DPR in the maxillary region, but did not differ significantly in the mandibular region. Conclusions: Presurgical planning can be performed safely using DPR in the mandible; however, presurgical planning using CBCT is recommended in the maxilla when a structure in a buccolingual location needs to be evaluated because this imaging modality supplies buccolingual information that cannot be obtained from DPR.

• Molecules and Cells
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• 제45권10호
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• pp.749-760
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• 2022

Osteoclast generation from monocyte/macrophage lineage precursor cells needs to be tightly regulated to maintain bone homeostasis and is frequently over-activated in inflammatory conditions. PARK2, a protein associated with Parkinson's disease, plays an important role in mitophagy via its ubiquitin ligase function. In this study, we investigated whether PARK2 is involved in osteoclastogenesis. PARK2 expression was found to be increased during the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. PARK2 gene silencing with siRNA significantly reduced osteoclastogenesis induced by RANKL, LPS (lipopolysaccharide), TNFα (tumor necrosis factor α), and IL-1β (interleukin-1β). On the other hand, overexpression of PARK2 promoted osteoclastogenesis. This regulation of osteoclastogenesis by PARK2 was mediated by IKK (inhibitory κB kinase) and NF-κB activation while MAPK (mitogen-activated protein kinases) activation was not involved. Additionally, administration of PARK2 siRNA significantly reduced osteoclastogenesis and bone loss in an in vivo model of inflammatory bone erosion. Taken together, this study establishes a novel role for PARK2 as a positive regulator in osteoclast differentiation and inflammatory bone destruction.

• 대한심미치과학회지
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• 제7권1호
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• pp.64-70
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• 1998

Recently as the interest on Esthetic Dental Prosthesis is arising, the domains of Esthetic Dentistry is being widely investigated. Esthetic Dental Prosthesis is influenced greatly by the shape, color, tooth arrangement of the teeth and the facial features(including the lips). So the degree to which these characters harmonize will be the professional esthetical standard while the satisfaction of the patient will be another esthetical measure. The reason for this is that each and every one of us has a different standard of what is considered beautiful. Of course it doesn't mean that every standard is correct. Then what does Esthetical Prosthesis mean and what should the standard be? This must be defined as a prosthesis that satisfies the basic requirements - margin, contour, occlusion, and at the same time it should restore the shape, color, and tooth arrangement which the client(patient) would love to have. As Esthetic Prosthesis contains its subjective meaning a great deal, it shouldn't be simply distinguished between the beauty of the teeth itself or ugliness. Also in some case, it needs surgical treatment to make it harmonious in the whole aspect so that one may keep the feeling of satisfaction and security. Then what is the shape, color, tooth arrangement that each individual wants? There is an indefinite variety. For example, considering arrangement both regular and irregular is considered beautiful by each different individual. Regular arrangement may be the standard of beauty for some, while irregular arrangement may be thought of as natural looking and beautiful. That is why there must be enough communication with the patient and an agreement be made at the clinic before a diagnostic plan and actual surgery. The treatment plan as mentioned above must be sent to the dental laboratory. In this research, by using case studies, I am going to the importance and appropriateness of the data and information for the dental technician's esthetic prosthesis.

• 한국치위생학회지
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• 제11권4호
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• pp.533-546
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• 2011

Objectives : The purpose of this study was to examine the oral health knowledge, attitude, behavior among 918 secondary students and their needs for oral health education in Seoul, Gyeonggi Province and Choongbuk Province. Methods : The collected data were analyzed by the statistical package SPSS 18.0, and frequency analysis, correlation analysis, crosstabs, t-test and ANOVA were utilized. Results : The girls proceeded the boys in oral health knowledge, and the high school students were ahead of the middle schoolers in oral health knowledge, attitude and behavior. Those who ever received oral health education surpassed the others who didn't in oral health knowledge and behavior(p<0.01). The students hoped to be provided with oral health education by dental hygienists during regular classroom hours once per semester, 30 minutes to one hour at a once, and their favorite ways of oral health education were videotape watching and practice. As for needs for oral health education, the middle school students had higher needs for that than the high schoolers, and the former's needs scores were above the average(p<0.05). Conclusions : There were differences among the students in oral health knowledge, attitude and behavior according to their school system, gender and oral health education experiences, but oral health education was provided without taking their differences into account. It was recommended, efficient oral health education programs should be developed by focusing on how to take care of and prevent oral diseases, and videotape watching and practice that were preferred by the secondary students should be included in the programs.

• 한국치위생학회지
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• 제12권1호
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• pp.157-165
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• 2012

Objectives : The purpose of this study was to examine the professors, who teach the dental hygiene program in Korea, on the awareness of the research ethics education check. And attempt to provide and promote a basic foundation for future research ethics education Methods : Questionnaire survey was carried out targeting 119, who teach the dental hygiene program. The collected data was performed frequency & percentage, independent t-test and one-way ANOVA, Pearson's correlation coefficient and multiple regression. Results : 1. As recognition about research ethics education needs, they expressed the biggest recognition that research ethics education is required($3.66{\pm}0.57$) 2. Regarding the correlation between students needs research ethics education and interested research ethics education had a statistically significant correlation of r=0.381 which was the highest correlation factor. 3. Research ethics education taking institutions, 39.4% respondents experienced the biggest national research institutes. 4. Between general characteristics and research ethics education recognition level, they were statistically significantly different with age and major course(p<0.05). 5. The affecting factors on the research ethics education were teaching career and number of articles published as the first author, explained 12.8%(p<0.001). Conclusions : Research ethics education is desperately needed. Therefore I will insist the case based approach in the research ethics education program with the format of a stand course.

• 대한소아치과학회지
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• 제35권2호
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• pp.367-375
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• 2008

교정치료 시 고정원은 항상 염두에 두면서 치료를 진행해야 하는 중요한 요소이다. 전통적인 고정원을 이용한 치료는 환자의 적극적인 협조를 필요로 하고 원하는 치아이동에 대한 반작용이 나타날 수 있는 등의 부작용을 가지고 있다. 그러므로 보다 견고한 구강 내 고정원이 요구되어져 왔으며 이를 위해 miniscrew가 임상에서 흔히 이용되고 있다. Miniscrew를 통한 고정원의 확보는 구외력 의존도 감소, 치료기간의 단축, 식립 후 즉시 교정력 적용, 환자의 협조도 불필요, 식립의 간편성, 저렴한 비용 등의 장점을 가지고 있다. 그러나 성장기 환자는 성인에 비해 골질이 좋지 않아 miniscrew의 성공률이 성인에 비해 낮다. 그러나 일단 고정에 성공하면 많은 교정치료 시 매우 유용하게 이용할 수 있다. 본 증례는 혼합치열기 환자를 miniscrew를 이용하여 정중이개 및 정중선 불일치, 매복치에 대한 양호한 교정치료를 하였기에 보고하는 바이다.

• 대한장애인치과학회지
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• 제6권2호
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• pp.77-83
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• 2010

This article discusses the issues of benefit and risk associated with outpatient general anesthesia and deep sedation for the special need dental patients. The purpose of administering anesthesia for patients with special needs is to provide effect dental treatment. But there are many complications such as sore throat, nausea and vomiting, airway trauma, airway obstruction and hypoxic brain damages, etc. In order to decrease incidence of complication, before general anesthesia meticulous patient evaluation is much important. But, there are a number of factors that make it difficult to accurately assess the anesthetic risk for many people with special needs. These include limited medical workups, uncooperative behavior, and difficulties in postoperative cares, etc. But Judging from several years experience of many contries, it appears that the incidence of mortalities for people with special needs in dental setting is minimal and the incidence of morbidity is limited. In the long run, the delivery of general anesthesia and deep sedation for people with special needs can be considered a very safe and successful procedure.

• 대한치과기공학회지
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• 제34권3호
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• pp.315-324
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• 2012

Purpose: The purpose of this study was to survey dental prosthesis and dental prosthesis needs of elderly for improving oral health status. Methods: The data collected from 'The fifth Korean national health and nutrition examination survey 2010' was analyzed in this study. Statistical analysis was done using the Statistical Package for Social Sciences version 19.0 for Windows. We determined frequencies and percentage, calculating means, and standard deviations, and determined statistical significance using cross-tabulation analysis, logistic regression analysis. Results: General characteristics showed differences in mandible fixed crown bridge needs associated with periodontal disease. General characteristics showed differences in maxillar partial and full denture with gender, age, education, perceived oral health. General characteristics showed differences in mandible partial and full denture with age, residence, education, perceived oral health. Conclusion: In order to improve oral health of the elderly, Dental prosthesis support policy and oral health policy are necessary.

• 한국산학기술학회논문지
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• 제15권7호
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• pp.4353-4360
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• 2014

이 연구는 우리나라 노인의 구강건강 개선을 위하여 현재 저작 불편 호소와 치과 보철 필요와의 관련성을 평가하고자 하였다. 연구대상자는 제5기 1차년도 국민건강영양조사에 참여한 65세 이상 노인 1,177명을 대상으로 조사를 실시하였다. 구강검사를 통하여 상실치아와 필요 보철 상태를 파악하였으며, 구조화된 설문도구를 이용하여 사회경제요인, 구강건강 관심도, 저작능력과 발음문제를 조사하였다. 수합된 자료는 SPSS 19.0 프로그램을 사용하여 분석하였다. 우리나라 노인의 42.9%는 저작 불편을 호소하였으며, 로지스틱 회귀분석을 통하여 혼란변수를 보정한 결과 고정 보철 필요 위험비는 1.22, 부분의치 필요 위험비는 2.47, 총의치 필요 위험비는 2.06이었다. 치과보철 필요는 저작 불편 호소와 관련이 있었다. 따라서 노인을 위한 치과 보철 정책과 구강건강증진의 뒷받침이 가장 필요하다.